Летом в пустыне часто бывает жарко.

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Breakdown of Летом в пустыне часто бывает жарко.

• часто: often
• жаркий: hot
• летом: in the summer

Questions & Answers about Летом в пустыне часто бывает жарко.

Why is it летом and not лето to mean “in summer”?

Летом is the instrumental-case form of лето (“summer”) used in a special time expression meaning “in (the) summer / during summer”.

Russian often uses the instrumental case without a preposition to talk about time when something happens, particularly with seasons and parts of the day:

• летом – in (the) summer
• зимой – in (the) winter
• весной – in (the) spring
• осенью – in (the) autumn
• днём – in the daytime
• утром – in the morning
• вечером – in the evening

So Летом at the start of the sentence means “In summer / In the summertime”. Using just лето here would sound ungrammatical.

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Could we say в лето instead of летом?

No, в лето is not the normal way to say “in summer” in modern Russian.

For seasons and similar time periods, Russian prefers those special instrumental forms (летом, зимой, etc.) with no preposition.

В + accusative/prepositional is used with many other time expressions:

• в мае – in May
• в 2020 году – in 2020
• в субботу – on Saturday

But for seasons you should memorize the adverb-like forms: летом, зимой, весной, осенью.

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